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Longstem evening primrose

Oenothera longissima

Also called Long Stem Evening Primrose

Longstem evening primrose
Photo: Stan Shebs, CC BY-SA 3.0

Oenothera longissima is a tall biennial or short-lived perennial wildflower from the southwestern and west-central United States, grown for its large yellow evening flowers. It does best in full sun with well-drained soil and room for its tall stems.

Family
Onagraceae (Evening-primrose family)
Grows as
Perennial
Light
Full sun, Part shade
Water
Water regularly while establishing, then less often; avoid soggy soil.
Soil
Well-drained, sandy or loamy soil.
Temperature
10–35 °C; hardy to about -15 °C in mild winters.
How easy
Easy
Native range
SW. & WC. U.S.A.
Climate
temperate

About

Oenothera longissima is a species of flowering plant in the evening primrose family known by the common name longstem evening primrose. It is native to the southwestern United States, where it grows in relatively moist areas in scrub and woodland habitat. This is a biennial herb producing a tall, erect stem known to well exceed 2 meters in height. The widely lance-shaped leaves may be 22 centimeters in length and may have slight teeth along the edges. The inflorescence is a spike of showy large flowers. Each has yellow petals which may be more than 6 centimeters in length and fade orange or red with age. The fruit is a lance-shaped capsule up to 5.5 centimeters long.

Other Oenothera plants

Common evening primrose · Tufted Evening Primrose · Antioch Dunes evening primrose · Birdcage evening primrose · Beach evening primrose · Hooker's evening primrose · Narrowleaf evening primrose · Redsepal evening primrose · Cutleaf evening primrose · Lindheimer's Beeblossom · Threadleaf evening primrose · Bigfruit evening primrose

Text excerpted from the Wikipedia article Oenothera longissima by its contributors, under CC BY-SA 4.0; the excerpts and the care summary drawn from them are shared under the same licence.

The care summary was written by AI (Claude, Anthropic) from the sources on this page, with general growing knowledge where they are silent. Check before relying on it.

Life form, climate and native range: World Checklist of Vascular Plants, Royal Botanic Gardens, Kew (CC BY 3.0), reformatted; see Plants of the World Online.

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